Readers of hardcopy documents, such as books, magazines and newspapers, commonly make handwritten marks to highlight, underline, strike-through and circle text, along with other mechanical markings. Such mechanical markings may, for example, indicate important text that the reader may wish to revisit at a later time or share with another person. Some people spend a considerable amount of time and effort in marking-up important text. For instance, in the publishing industry, a common practice for editors is to use hard copies for correcting mistakes, highlighting areas to be edited or annotating paragraphs for layout. After the editing or other annotation process, the marked up hardcopy can be converted into digital form, such as by scanning or otherwise imaging the marked up hardcopy. However, when the hardcopy is scanned and converted to, for example, Portable Document Format (PDF) using existing techniques (e.g., optical character recognition or other process of generating digital text), the mechanical markings are not retained in the digital version of the document. The loss of the markings can represent a significant loss of information.